Railway signaling.



J. P. BUCHANAN.

RAILWAY SIGNALING.

APPucATloN HLED MAYI. 1914.

1,177,377. Pmnted Mar. 28,1916.

Wfww 1 mm 7 i. trolled by track circuits."

UNTTED sTATEs PATENT oEEToE.

JOHN P. BUCHANAN, OF CLEVELAND, OHIO, ASSIGNOR 0F ONE-HALF '10 FREDERICK IB.

WIEGAND, OF CLEVELAND, OHIO.

RAILWAY SIGNALING.

specification of Letters Patent. Y Patented Mar, 28, 1916 Original application led 0ctober29, 1913,*Seria1 No. 797,988. Divided and this application ledMay '7,

1914. Serial No. 836,935.

Sand useful Improvements in Railway Signaling, of which the following is a specification.

My invention relates to railway signaling of the type in which the signals are con- More particularly, my invention relates to signaling of'this type in'which a block between s1gna1s is divided into. two or more sections each of which is provided with an isolated track circuit.

The present application is a division of my co-pending a plication filed October 29, 1913, Serial No. 797,988, for relays.

I will describe one form of signalmg system embodying my invention, and will then point out thel novel features thereof 1n claims.

The 4accompanying drawing is a diagrammatic view showing one form of signaling system embodying my invention.

Referring to the drawing, I have here shown a stretch of. railway track which is divided into successive blocks A-B, B- C, etc. Located adjacent the entrance ends of the blocks are railway signals SA, SB, etc., each of which is adapted to indicate dangerf caution and clear;vas here shown, 'these signals are of the semaphore type and each signal^comprises a single arm 4adapted to assume three indicating positions, but it is understood that any type of signal adapted to give the three said indications may equally well be employed.

Each block is divided into two sections, the sections for block A--B bengA-a and (Ir-B, and those for the other blocks being similar. As here shown, the rails of each section are electrically isolated vfrom those of the ,adjacent sections by insulated joints 2.

' Each section is provided as usual with a track circuit4 comprising the rails of the section, asource of current 35er 36 (here h wn as beingJ batteries) and a relay R or lt. The relay R for the iirst section of each block controls the signal for the corresponding block, and may be of any. suitable type adaptedto assume three controlling positions; for example, each of these relays may be of the type shown in my application Serial No. 797,988, of which the present' application is a division, the contact arrangement being the same as that shown in Fig. 3, except that contacts 22, 3l and 32 are omitted. Each of these relays comprises a winding 11 connected with the track rails, and a contact 21 which closes the caution indication circuit of the signalwhenthe relay is energized in one direction and both the 'Caution and clear indication circuits when the relay is energized in the other direction. 'Therelay R for the section at the exit end of each block is employed to control the supply of current to the rails of the section in the rear, and as here shown these relays are of the type-shown in my application, Serial No. 797,988, the contact arrangement being the same as that shown in Fig. 5 of said application. Briefly described, each of these relays comprises a winding 11 connected with the track rails, a cam 19a actuand are swung in one direction or the other from this middle position when the winding is energized in one direction or the other. The cam and lingers are so arranged that when the armature occupies its middle position, both fingers touch a contact 26; when the armature swings in one direction the cam 19L moves finger' 31b away from contact 26 and into engagement with contact 28; and when the armature swings in the other direction the cam moves the other finger 32b away from contact 26 and into engagement with contact 27. The contact fingers 3lb and 32b are connectedrv with the track rails respectively, one terminal of battery 36 is connected with contact 26, and the other battery terminal is connected with both contacts 27 .and 28. Hence,'whenthe relay armature is swung to one extreme position or the other, battery 36 is connected with the' track rails in one direction or the other, .and when the armature occupies its middle position the battery is disconnected from the rails and the rails are connected by a low-resistance shunt comprising ngers 31h and 32h and contact 26, Each signal operates a pole-changer for reversibly connecting the battery 35 'with the rails of the track section immediately in the rear ot' the Signal; the battery 35 is connected with. the rails in one direction when the signal indicates clear and caution, and in the other direction when the signal indicates danger.

The operation of the system is as 'fols lows: Since the section at the eXit end oi the block at the right-hand end of the drawing is occupied by a train lV, relay R- for this section is deenergized, so that the battery 3G is disconnected from the rails of section C-c, and the rails of this section are connected by a low-resistance shunt. Re lay R for section CY-c is therefore denergized so that signal SC indicates danger.

Pole-changer P operated by this signal then connects battery 35 with the rails of the section b--O in the rear in such direction that contactlb of relay R for this section moved into engagement with Contact 23. Relay R for section B-o is then energized in such direction as to cause signal SB to indicate caution. The pole-changer P operated by this signal is therefore in such position that relayv R for section a-B is energized in the direction opposite to that of the corresponding relay for block -C so that relay R for section A-a is energized in suchdirection as tocause signal Stto ;ndicate Clear.

It will be noted that when the car or train occupies the section at the exit end of a block the rails of the other section for such block are placed on short circuit by the relay R so that this relay is the equivalent of a car or train on the latter section and. the possibility of false operation of the relay for the latter section by stray or foreign current is greatly reduced.

Although l have herein shown and described only one form of railway signaling system embodying my invention, it is understood that `Various changes and modiications may be made therein Within the scope of the appended claims Without departing from the spirit and scope of my invention.

Having thus described my invention, What I claim is:

l. In combination, tivo sections` of a rail- Way track, a source of current, means for reversibly connecting said source with the track rails of one section, a relay energized yfrom the rails of the same section and having a member adapted to assume a middle position when therelay is de'e'nergized and to move in one direction or the other from alweer said position when the relay is energized in one direction or thel other, a source of current for the other section, and contacts ineluded .in .said relay and controlled by said member for placing the .rails of the latter section on short circuit when the member occupies its middle position, and for connecting said latter source of current with the rails of the latter section in one direction 'or the other when the meniber'moves in one direction or the other from its middle position.

:in combination, a railway track seo tion, a. source of current, a relay having a member adapted to assume a middle position when the relay is denerg'ized and to move in one direction or the other therefrom when the relay is energized in one direction or the other, means for Vrewersibly energizing said relay, and contacts included in said Se relay and controlled by said member t'or placing the rails of said ytrack section on short circuit when said member oc J middle position, and for connecting said source of current with said rails in one di- 85 reetion yor the other *when the member is@ moved in one direction or the other from its middle position.

3. En combination, two sections of rail-` i vz track, a source ol current for one of Y90 said sections, inea 'is for reyersibly connecting sain source 'with the track rails oit said section; a relay energized trom the rails of the same section and having a member adapted to assume middle positionvvhen the relay is denergized and to .move in one direction or the other from said position when the relay is energized in one direction or the other, a central stations ry contact and two outside stationary contacts, a source lot current having one terminal connected with said centralr Contact andthe other terminal connected with both outside contacts, two contact springs biased to engagement with respeo FB. VIEGAND, L: Q. Bienne. 

